# rehype-sort-attribute-values
[![Build][build-badge]][build]
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[![Downloads][downloads-badge]][downloads]
[![Size][size-badge]][size]
[![Sponsors][funding-sponsors-badge]][funding]
[![Backers][funding-backers-badge]][funding]
[![Chat][chat-badge]][chat]
**[rehype][]** plugin to sort attribute values.
## Contents
* [What is this?](#what-is-this)
* [When should I use this?](#when-should-i-use-this)
* [Install](#install)
* [Use](#use)
* [API](#api)
* [`unified().use(rehypeSortAttributeValues)`](#unifieduserehypesortattributevalues)
* [Example](#example)
* [Syntax](#syntax)
* [Syntax tree](#syntax-tree)
* [Types](#types)
* [Compatibility](#compatibility)
* [Security](#security)
* [Contribute](#contribute)
* [License](#license)
## What is this?
This package is a plugin that sorts attribute values, which optimizes for
repetition-based compression (such as GZip).
## When should I use this?
You can use this plugin when you want to improve the transfer size of HTML
documents.
## Install
This package is [ESM only][esm].
In Node.js (version 16+), install with [npm][]:
```sh
npm install rehype-sort-attribute-values
```
In Deno with [`esm.sh`][esm-sh]:
```js
import rehypeSortAttributeValues from 'https://esm.sh/rehype-sort-attribute-values@5'
```
In browsers with [`esm.sh`][esm-sh]:
```html
```
## Use
On the API:
```js
import rehypeParse from 'rehype-parse'
import rehypeSortAttributeValues from 'rehype-sort-attribute-values'
import rehypeStringify from 'rehype-stringify'
import {read} from 'to-vfile'
import {unified} from 'unified'
const file = await unified()
.use(rehypeParse)
.use(rehypeSortAttributeValues)
.use(rehypeStringify)
.process(await read('index.html'))
console.log(String(file))
```
On the CLI:
```sh
rehype input.html --use rehype-sort-attribute-values --output output.html
```
On the CLI in a config file (here a `package.json`):
```diff
…
"rehype": {
"plugins": [
…
+ "rehype-sort-attribute-values",
…
]
}
…
```
## API
This package exports no identifiers.
The default export is `rehypeSortAttributeValues`.
### `unified().use(rehypeSortAttributeValues)`
Sort attribute values.
###### Returns
Transform ([`Transformer`](https://github.com/unifiedjs/unified#transformer)).
## Example
###### In
```html
```
###### Out
```html
```
## Syntax
HTML is parsed according to WHATWG HTML (the living standard), which is also
followed by all browsers.
## Syntax tree
The syntax tree used is [hast][].
## Types
This package is fully typed with [TypeScript][].
## Compatibility
Projects maintained by the unified collective are compatible with maintained
versions of Node.js.
When we cut a new major release, we drop support for unmaintained versions of
Node.
This means we try to keep the current release line,
`rehype-sort-attribute-values@^5`,
compatible with Node.js 16.
## Security
As **rehype** works on HTML and improper use of HTML can open you up to a
[cross-site scripting (XSS)][xss] attack, use of rehype can also be unsafe.
Use [`rehype-sanitize`][rehype-sanitize] to make the tree safe.
## Contribute
See [`contributing.md`][contributing] in [`rehypejs/.github`][health] for ways
to get started.
See [`support.md`][support] for ways to get help.
This project has a [code of conduct][coc].
By interacting with this repository, organization, or community you agree to
abide by its terms.
## License
[MIT][license] © [Titus Wormer][author]
[author]: https://wooorm.com
[build]: https://github.com/rehypejs/rehype-minify/actions
[build-badge]: https://github.com/rehypejs/rehype-minify/workflows/main/badge.svg
[chat]: https://github.com/rehypejs/rehype/discussions
[chat-badge]: https://img.shields.io/badge/chat-discussions-success.svg
[coc]: https://github.com/rehypejs/.github/blob/main/code-of-conduct.md
[contributing]: https://github.com/rehypejs/.github/blob/main/contributing.md
[coverage]: https://codecov.io/github/rehypejs/rehype-minify
[coverage-badge]: https://img.shields.io/codecov/c/github/rehypejs/rehype-minify.svg
[downloads]: https://www.npmjs.com/package/rehype-sort-attribute-values
[downloads-badge]: https://img.shields.io/npm/dm/rehype-sort-attribute-values.svg
[esm]: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c
[esm-sh]: https://esm.sh
[funding]: https://opencollective.com/unified
[funding-backers-badge]: https://opencollective.com/unified/backers/badge.svg
[funding-sponsors-badge]: https://opencollective.com/unified/sponsors/badge.svg
[hast]: https://github.com/syntax-tree/hast
[health]: https://github.com/rehypejs/.github
[license]: https://github.com/rehypejs/rehype-minify/blob/main/license
[npm]: https://docs.npmjs.com/cli/install
[rehype]: https://github.com/rehypejs/rehype
[rehype-sanitize]: https://github.com/rehypejs/rehype-sanitize
[size]: https://bundlejs.com/?q=rehype-sort-attribute-values
[size-badge]: https://img.shields.io/bundlejs/size/rehype-sort-attribute-values
[support]: https://github.com/rehypejs/.github/blob/main/support.md
[typescript]: https://www.typescriptlang.org
[xss]: https://en.wikipedia.org/wiki/Cross-site_scripting